This article was written by Elizabeth Poulson, MPRB Naturalist at North Mississippi Regional Park
Have you seen any large, low-flying birds over your neighborhood lately? Often times a solitary bird, but sometimes seen in pairs? Recently, the naturalists at North Mississippi Regional Park have been receiving quite few questions about Great Blue Herons. Have they been seen in the park yet this spring? Do they stay all winter? Will they nest in the park again? So many great questions!
The short answer to a few of these inquiries is, yes, herons have frequently been seen flying over the park in recent weeks. Though there can be some Great Blue Herons that stay year-round in Minnesota, it’s likely that most are returning from down south now that the ice on the Mississippi River is gone and fishing will be much easier. As for nesting in the park again, unfortunately that is unlikely anytime soon. The herons flying over the park are probably on their way to their new nesting site, or rookery, just a couple miles downriver.
Until about eight years ago, North Mississippi Regional Park hosted a large colony of Great Blue Herons at what was known as Heron Island. This island is situated just north of the Camden Bridge, and offered a protected environment where the herons could raise their young. Nests are built out of sticks at the tops of tall and mature trees. Building the nests up high provides great protection away from ground predators such as raccoons, which will eat heron eggs and young. The proximity of the island to the riverbank also made it a great viewing spot to catch a glimpse of a day in the life of a Great Blue Heron.
Heron Island was first colonized in 2003 and grew to about 75 nests in 2009. By 2011, that number had grown to almost 180 nests. In May of 2011, the heron rookery was sadly destroyed in the tornado that hit North Minneapolis hard and took out many mature trees. Though the nesting site was decimated, many of the surviving herons have since joined up with sandpipers and peregrine falcons on an island just down river from the old rookery near Marshall Terrace Park or moved to the rookery farther up river at the Coon Rapids Dam.
The fact that this new rookery was established so quickly after the previous one was destroyed is a testament to the resilience of these stately birds to changes in their environment. Historically, Great Blue Herons were victims of unrestricted hunting early in the 20th Century and the effects of harmful pollutants like DDT a few decades later. However, today with greater awareness about conservation and legal protection, they are amongst the most common wading birds in North America. They have become a symbol of species recovery as well as clean water and healthy ecosystems due to their need for clear water in which to hunt.
As with many wildlife species, the Great Blue Heron inhabits a dynamic, ever-changing and human-dominated environment. Their dependence on wetlands, lakes, rivers and relatively isolated nesting sites makes them vulnerable to disturbances. Habitat loss and impacts such as increased traffic, motorboats, wetland dredging, water pollutants and other causes of reduced water quality are the largest threats to nesting colonies.
To learn about Great Blue Herons and their changing environment, or about the old and new rookeries, visit us at North Mississippi Regional Park. Check out a pair of binoculars for free from the front desk to look for herons flying overhead. Try out a bird watching hike with a naturalist the first Saturday each month to find out about the birds in our area. The park also offers free naturalist programs on a range of topic for families and adults each weekend; stop by and find your nature niche. If you have young children, then try out our Nature Nuts playgroup for kids (under age six) with an adult to explore the outdoors while learning about seasons, plants and animals. Summer camp registration is open—sign kids ages 6-12 up for nature day camps to explore, get messy and learn by doing!
May Public Programs –Free for all ages unless otherwise noted!
May 4—Spring Migration Bird Watching, from 8:30-10 a.m. Look for summertime birds or others that are just passing through.
May 11—Signs of Spring Hike, from 1-2 p.m. Explore the park to look for quick changing signs of spring.
May 16—Homeschool Day: Reptile or Amphibian, from 1-3 p.m. Compare and contrast the difference between reptiles and amphibians. Registration $5, for ages 5-13.
May 18—Nature Art: Fairy Gardens, 1:30-3 p.m. Add a touch of whimsy to your world by crafting a living work of art! Registration $10.
May 25—Outdoors: Fantastic Fish, 2-3:30 p.m. Dive into the world of Minnesota’s native fish, learning about river and lake habitats.
Find registration for these programs and more at minneapolisparks.org or call 612-370-4844 for more details. Do you have a question about nature in your own backyard? Then send it our way by emailing northmississippi@minneapolisparks.org and it could appear in a future article. Like us on Facebook to stay in the loop about what is happening at your park.